I have two questions about two circles.
A.First circle shows half a line measuring 4mm using 3.14 for pie. I came up with an answer that is wrong.:(
B.Second circle same pie but with a line all the way across the circle measuring 18cm. I got this one wrong?
Please help with steps on each? I want to understand what I got wrong so I can do better.
What questions are you trying to solve?
Circumference? Area? ??
area
A. Radius = 4
A = pi * r^2
A = 3.14 * 4^2
A = 3.14 * 16
A = 50.24 sq. cm.
B. Radius = 9 cm
Solve this the same was that I solved A.
I really understand thank you.
You're welcome. :-)
Sure, I can help you understand why you got the answers wrong for both circles. Let's go through each question step by step.
A. First circle with a half line measuring 4mm using 3.14 for pi:
To find the circumference of a circle, you need to use the formula:
C = 2 * pi * r
In this case, since you have a half line, it means you are looking for half the circumference of the circle. Therefore, you need to divide the formula by 2:
C/2 = pi * r
Given that you have a line measuring 4mm, which is equal to the radius (r), you can now substitute the values into the equation:
C/2 = 3.14 * 4
C/2 = 12.56
To find the value of C (the circumference), you need to multiply both sides by 2:
C = 12.56 * 2
C = 25.12 mm
So, the correct answer for the first question is 25.12 mm.
B. Second circle with a line all the way across the circle measuring 18cm using 3.14 for pi:
In this case, you want to find the full circumference of the circle using the given line measurement. The formula for the circumference is the same:
C = 2 * pi * r
Since you have the line all the way across (equivalent to the diameter), you can directly substitute the value into the formula:
C = 2 * 3.14 * 18
C = 113.04 cm
So, the correct answer for the second question is 113.04 cm.
Based on the explanations above, it seems like you might have misunderstood the concept of finding the circumference of a circle and how to apply it correctly in these two scenarios. I hope this helps you understand the steps and where you went wrong. If you have any further questions, feel free to ask!